Make url_base and root_doc consistents in testing env

[cedric-anne]

Checklist before requesting a review

• I have read the CONTRIBUTING document.
• I have performed a self-review of my code.

Description

The initial url_base in the testing env was http://localhost/glpi (as defined in the empty_data.php file, but the execution through tests/run_tests.sh script was changing it to http://localhost:80 (to match the actual address available through docker). Depending on how the tests were executed, some tests were failing.

To prevent unexpected test failures, I changed the default url_base from http://localhost/glpi to http://localhost/ in the empty_data.php file, so whatever the way the tests are executed, the CFG_GLPI['url_base'] and the CFG_GLPI['root_doc'] will always be consistent.

[cedric-anne]

Removing the :80 port indication from the base URL in the E2E test context reveals an issue with the webcal URL computation. I fixed it in the second commit.

[SebSept]

👍🏼 fixes my prob with phpunit/functional/TicketTest.php testScreenshotConvertedIntoDocument